Photogrammetry is the science of making measurements from photographs. Surveying is the technique and science of accurately determining the terrestrial or three-dimensional space position of points and the distances and angles between them. These points are usually, but not exclusively, associated with positions on the surface of the Earth and are often used to establish land maps and boundaries for ownership or governmental purposes. Photogrammetry used in surveying provides an accurate measurement technique for both land-based and aerial surveying.
Stereo photogrammetry makes it possible to determine the three-dimensional coordinates of points on an object, or target. These are determined by measurements made in three or more photographic images taken from different positions. Common points are identified on each image. A line of sight can be constructed from the camera location to the point on the object. It is the intersection of these rays that determines the three-dimensional location of the point.
Despite the advances made in surveying instruments, a need exists in the art for methods and systems for surveying using stereo photogrammetry.